The three main types of installer are:
"Regular" Debian Installer: This is a normal Debian Live image with a separate kernel and initrd which (when selected from the appropriate bootloader) launches into a standard Debian Installer instance, just as if you had downloaded a CD image of Debian and booted it. Images containing a live system and such an otherwise independent installer are often referred to as "combined images".
On such images, Debian is installed by fetching and installing .deb packages using debootstrap or cdebootstrap, from the local media or some network-based network, resulting in a standard Debian system being installed to the hard disk.
This whole process can be preseeded and customized in a number of ways; see the relevant pages in the Debian Installer manual for more information. Once you have a working preseeding file, live-build can automatically put it in the image and enable it for you.
"Live" Debian Installer: This is a Debian Live image with a separate kernel and initrd which (when selected from the appropriate bootloader) launches into an instance of the Debian Installer.
Installation will proceed in an identical fashion to the "Regular" installation described above, but at the actual package installation stage, instead of using debootstrap to fetch and install packages, the live filesystem image is copied to the target. This is achieved with a special udeb called live-installer.
After this stage, the Debian Installer continues as normal, installing and configuring items such as bootloaders and local users, etc.
Note: to support both normal and live installer entries in the bootloader of the same live media, you must disable live-installer by preseeding live-installer/enable=false.
The man page says
--debian-installer true|cdrom|netinst|netboot|businesscard|live|false defines which type, if any, of the debian-installer should be included in the resulting binary image. By default, no installer is included. All available flavours except live are the identical con- figurations used on the installer media produced by regular debian-cd. When live is choosen, the live-installer udeb is included so that debian-installer will behave different than usual - instead of installing the debian system from packages from the medium or the network, it installs the live system to the disk.
So I am assuming I have that part correct and that I am missing something else.
My auto/config is attached, I have stripped sections that been suggested I did not need and will strip more after this coming weekend.
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